Early Christmas shopping - Saddlebag. Please HELP!

I'm doing a research to buy a leather/durable saddlebag for my significant other's first bike and could definitely use some help/input from people who know a thing or two about bikes. I'm pretty much a dummy when it comes to this so here I am, signed up for the forum. I'm thinking of the criteria listed below and wondering if anyone kindly has any suggestions on which saddle bag is the best for me at a reasonable price.

- Waterproof (must)
- Heat protection (must)
- Preferably with adjustable yolk
- Could be used as Throw Over or can be mounted.


I have a picture of his bike too (figured it would help) but don't know how to upload it here or if I even can. If you are kind enough to let me know, you guys are already awesome!

Thank you so much in advance of your input.